Call the town, and see what they say?

Some towns offer it at either the dump or their DPW barn.

I'm surprised they are giving out salt, but that is pretty cool if they do.

If you end up looking to buy salt, the cheapest I typically find are the 50 pound bags of vaporizer at HD. It's just plain old rock salt. They have two formulas of vaporizer-the 50 pound is cheaper than the 40 pound.

Lowes has some even cheaper 50 pound bags, but every time I go they are hardened into bricks.